Zinc absorption from glucose and amino acid dialysis solutions in children on continuous ambulatory peritoneal dialysis (CAPD).

Zinc deficiency in children with chronic renal failure may be due to inadequate intake or excessive losses. To determine the effect of dialysate solute type and concentration on the net absorption or loss of zinc from the peritoneal cavity, six CAPD patients ages 9-19 years were dialyzed with 1.3% and 2.3% amino acid-containing dialysis solutions and 2.5% and 4.25% glucose-containing solutions on four separate occasions. Zinc contamination of the initial effluent dialysis solutions was quite high (17.1 +/- 7.7 micrograms/dl) but did not differ between the four solutions. Significantly higher zinc retention was documented with the glucose-containing dialysis solutions compared to the amino acid-containing solutions (99.8 +/- 32.7 vs. 28.3 +/- 51.3 micrograms, 2.5% G vs 1.3% AA, p less than 0.01; 146.0 +/- 112.6 vs. 23.0 +/- 84.3, 4.25% G vs 2.3% AA, p less than .01). Although the mechanism is unclear, results of this study confirm in children that there is significant net absorption of zinc from glucose containing dialysis solutions at both high and low glucose concentrations. Thus, CAPD does not contribute to zinc depletion. Solute concentration did not affect net zinc absorption; thus it appears that movement of zinc across the peritoneum is dependent on solute type (amino acid or glucose) and independent of the osmolality.